Postoperative delirium risk in patients with hyperlipidemia: A prospective cohort study

Study objective: Hyperlipidemia and postoperative delirium (POD) significantly affect patients quality of life; however, the question of whether hyperlipidemia constitutes a risk factor for POD remain unclear. This study aimed to investigate whether patients with hyperlipidemia face elevated risks of developing POD and to identify potential cause for this increased risk.<br /> Design: A prospective cohort study.<br /> Setting Operating room.<br /> Patients: Patients were adults scheduled for colorectal cancer surgery in 2023.<br /> Exposures: The exposure factor was hyperlipidemia, and the patients were divided into hyperlipidemia group and non-hyperlipidemia group.<br /> Measurements: POD occurrence within three days post-surgery was assessed using the 3-Minute Diagnostic Interview for Confusion Assessment Method. Over one year, these patients were monitored through telephone to evaluate their survival and cognitive function. Logistic regression analysis was performed to evaluate the risk factors for POD development in patients with hyperlipidemia and to construct a clinical prediction model<br /> Main results: This study included 555 patients. POD incidence was 21.69% in the hyperlipidemia group and 12.7% in the non-hyperlipidemia group. One year following surgery, patients with hyperlipidemia and POD exhibited significantly higher rates of mortality and cognitive decline than did those without POD (p < 0.001). A multi- factorial logistic clinical prediction model was constructed from seven independent risk factors for POD development in patients with hyperlipidemia, including education, preoperative total cholesterol (TC), preoperative triglyceride (TG), diet, history of hypertension, Sedation-Agitation Scale, and postoperative trimethylamine N- oxide expression level, and it had the highest predictive value for POD development in patients with hyperlipidemia.<br /> Conclusions: Compared with those without hyperlipidemia, patients with hyperlipidemia had higher POD incidence. Elevated serum TC and TG levels are independent risk factors for POD in patients with hyperlipidemia. The study's findings could help develop strategies for improving POD and hyperlipidemia treatment